The short version of 胸腺素α1 fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-03-18. Anything still debated is marked as such rather than presented as settled.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids, corresponding to the N-terminal fragment of prothymosin alpha. Its sequence begins with acetylation at the N-terminus, a modification that affects stability and receptor interaction. The peptide is acidic, with a calculated isoelectric point near 4.2, and carries no disulfide bonds, so its secondary structure is largely flexible in solution. Molecular mass is approximately 3108 daltons. The native form was first isolated from bovine thymus tissue, while pharmaceutical material is produced by solid-phase peptide synthesis.
Within the immune system, the peptide acts on several cell types rather than a single target. Reported activities include promotion of T-cell maturation, enhancement of natural killer cell activity, and modulation of cytokine production by dendritic cells and macrophages. Some of these effects appear to operate through toll-like receptor signaling, though the precise receptor-level mechanism remains debated. Whether the observed immune changes translate into clinical benefit is a separate question and depends on the indication studied.
Thymosin alpha-1 is a short peptide of 28 amino acid residues first described in the 1970s as a component of thymic extracts. Its N-terminal residue carries an acetyl group, and the sequence is highly conserved across mammalian species. The peptide is not encoded as a standalone gene product; it is released by proteolytic cleavage from the N-terminus of prothymosin alpha, a larger acidic nuclear protein. That precursor relationship places it within a broader family of thymic and immune-associated peptides that have been studied for decades.
The activity of this peptide is generally described as immunomodulatory rather than directly antimicrobial. Experimental work links it to signaling through certain Toll-like receptors on dendritic cells and to downstream maturation of antigen-presenting cells. Reported effects include expansion of T cell subsets, shifts in cytokine profiles, and increased natural killer cell activity. These observations come largely from cell culture and animal models, and the precise receptor-level events in humans remain incompletely characterized.
The compound has been investigated as an adjunct in chronic viral hepatitis and as a vaccine adjuvant, with results that vary by study design and population. Regulators in some countries have approved a synthetic form for specific indications, while other agencies have not. Whether the peptide produces consistent clinical benefit across diverse patient groups is still an open question, and many trials have been small. Its status is therefore best described as investigational in many contexts and established only narrowly.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic peptide, 28 residues | N-terminal fragment of prothymosin alpha |
| Molecular mass | About 3108 Da | Acetylated form |
| Isoelectric point | Near 4.2 | Acidic peptide |
| Appearance | White to off-white lyophilized powder | Common supplied form |
| Typical storage | -20 °C or below, dry | Solution stability is lower |
市售的胸腺素α1通常以冻干粉形式提供，溶解后用于注射。其氨基酸组成包括多个酸性残基，因此在中性pH下带负电荷。该肽可溶于水和生理盐水，但在有机溶剂中溶解度有限。储存条件通常为冻干状态下负20摄氏度，溶解后需冷藏并避免反复冻融。常见的同义词包括胸腺肽α1、thymalfasin和Tα1。
胸腺素α1（thymosin alpha 1，Tα1）是一种由28个氨基酸组成的酸性肽，N端被乙酰化，分子量约为3108道尔顿。该肽最早从牛胸腺组织提取物中分离，属于胸腺素组分5的一个成分。其序列在不同哺乳动物中高度保守，提示其具有基本的生物学功能。名称中的“α1”指其在电泳中的迁移位置，并非表示亚型编号。它既存在于胸腺，也存在于脾脏和淋巴结等免疫组织。
20世纪70年代，研究者从胸腺提取物中纯化出多种小肽，Tα1是其中被较早表征的一种。最初的制备依赖组织匀浆和层析步骤，产量低且成分复杂。随着固相肽合成技术成熟，实验室和工业界能够生产与天然序列一致的合成版本。合成肽的纯度可达95%以上，并可通过反相高效液相色谱和质谱进行鉴定。这一转变使研究不再依赖动物胸腺来源。
Identity and purity testing for thymosin alpha 1 relies mainly on reversed-phase high-performance liquid chromatography and mass spectrometry. Chromatography separates the parent peptide from truncated or modified variants, while mass spectrometry confirms the expected molecular mass. Amino acid analysis and peptide mapping provide additional sequence confirmation. Counterion content, water content, and residual solvents are measured separately as part of specification testing. No single method captures every attribute, so laboratories combine several techniques.
The peptide lacks cysteine, methionine, and tryptophan, so disulfide scrambling and sulfur oxidation are not major degradation routes. Instead, aspartate residues can undergo isomerization or cyclization to succinimide intermediates, generating isoaspartate variants. Hydrolysis of peptide bonds also occurs slowly in solution. These changes may reduce biological activity even when the main peak remains detectable. Stability studies therefore track both potency and the appearance of related substances.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
Thymosin alpha-1 is supplied as a lyophilized powder in most research settings. The solid dissolves readily in water and in common aqueous buffers, and it is typically reconstituted shortly before use. Solutions are clear and colourless at ordinary working concentrations. Because the peptide is hygroscopic, weighing and reconstitution are usually performed with minimal exposure to ambient air. Aliquots are prepared to avoid repeated freeze-thaw cycles, and working solutions are kept cold.
Long-term storage is generally at minus twenty degrees Celsius or colder, preferably desiccated and protected from light. Lyophilized material is more stable than reconstituted solution, which degrades faster at room temperature. Stability depends on pH, ionic strength, and the presence of oxidising agents. Published stability data for the peptide are limited, so storage claims in catalogues should be treated as general guidance rather than measured guarantees. Freeze-thaw cycles are kept to a minimum.
Identity and purity are normally confirmed by reversed-phase high-performance liquid chromatography and mass spectrometry. The expected mass for the acetylated 28-residue peptide is close to 3108 daltons, and a mass shift indicates a modification or truncation. Peptide mapping after enzymatic digestion can resolve sequence-level questions. Counter-ion content, water content, and residual solvents are separate quality attributes that a certificate of analysis may or may not report. Aggregation is monitored by size-exclusion chromatography when relevant.
== History == EAS was founded in Pacific Grove, Monterey County, California in 1992 by biochemist Anthony Almada, and businessman Ed Byrd. In 2012, Byrd founded EAB Lab. After discovering the possible benefits for athletes of creatine monohydrate supplementation, in December 1992 they acquired a kilogram of creatine and began trials. In 1993, they released the first commercially available creatine supplement intended specifically for strength and muscle enhancement under the EAS brand name Phosphagain. The product caught the eye of Bill Phillips, publisher of Muscle Media 2000 (usually referred to as "MM2K"), and he began to write about its benefits in the Natural Supplement Review and his subscriber-based newsletters. In 1994 he purchased EAS from Almada and Byrd, and was 100% owner of EAS until the sale to North Castle Partners. Phillips' subscriber base was the platform in which to tout his new acquisition. He promoted the company's products through heavy editorial-style advertisements in MM2K. Led by products like Myoplex Protein Supplement, Phosphagen and HMB, this eventually made EAS significant in the nutritional supplement industry. In 1999, North Castle Partners purchased EAS for $160 million. Phillips retained about a third of the company, which he sold in 2004. In 2005, EAS was purchased by Abbott Laboratories for approximately $320 million in a cash-for-stock transaction and existed as a solely-owned division of Abbott. The refreshed product line focused on sports bars, drink mixes, and similar products.
Faisal did treat Palestine differently in his presentation to the Peace Conference on 6 February 1919 saying "Palestine, for its universal character, [should be] left on one side for the mutual consideration of all parties concerned". The agreement was never implemented. In a subsequent letter written in English by Lawrence for Faisal's signature, he explained:
The reaction involves adsorption of protons onto S8 clusters, followed by disproportionation into the reaction products. The second, fourth and sixth ionization energies of sulfur are 2252 kJ/mol, 4556 kJ/mol and 8495.8 kJ/mol, respectively. The composition of reaction products of sulfur with oxidants (and its oxidation state) depends on whether releasing of reaction energy overcomes these thresholds. Applying catalysts and/or supply of external energy may vary sulfur's oxidation state and the composition of reaction products. While reaction between sulfur and oxygen under normal conditions gives sulfur dioxide (oxidation state +4), formation of sulfur trioxide (oxidation state +6) requires a temperature of 400–600 °C (750–1,100 °F) and presence of a catalyst. In reactions with elements of lesser electronegativity, it reacts as an oxidant and forms sulfides, where it has oxidation state −2. Sulfur reacts with nearly all other elements except noble gases, even with the notoriously unreactive metal iridium (yielding iridium disulfide). Some of those reactions require elevated temperatures.
== Mechanism == As an aspartic protease, the dimerized HIV-1 PR functions through the aspartyl group complex, in order to perform hydrolysis. Of the two Asp25 residues on the combined catalytic active site of HIV-1 PR, one is deprotonated while the other is protonated, due to pKa differences from the micro-environment. In a general aspartic protease mechanism, once the substrate is properly bound to the active site of the enzyme, the deprotonated Asp25 catalytic amino acid undergoes base catalysis, rendering the incoming water molecule a better nucleophile by deprotonating it. The resulting hydroxyl ion attacks the carbonyl carbon of the peptide bond, forming an intermediate with a transient oxyanion, which is stabilized by the initially protonated Asp25. The oxyanion re-forms a double bond, leading to the cleavage of the peptide bond between the two amino acids, while the initially deprotonated Asp25 undergoes acid catalysis to donate its proton to the amino group, making the amino group a better leaving group for complete peptide bond cleavage and returning to its original deprotonated state. While HIV-1 PR shares many of the same characteristics as a non-viral aspartic protease, some evidence has shown that HIV-1 PR catalyzes hydrolysis in a concerted manner; in other words, the nucleophilic water molecule and the protonated Asp25 simultaneously attack the scissile peptide bond during catalysis.
Sources: en.wikipedia.org
==== Danish ==== Danish Brotherhood in America Danish Sisterhood - Founded December 15, 1883, in Negaunee, Michigan, by Mrs. Christine Hemmingsen. A supreme lodge was formed in 1887, and all the officers were women by 1910. Membership was open to women of Danish descent or married to a man of Danish descent. Admission is by black ball, with one blackball enough to disqualify; there is always a second ballot; if there is another blackball a selected secret committee is appointed to determine the cause. Had a secret ritual, and no uninitiated person may attend secret meetings of the lodge. Locals are called "lodges"; regional groups are called "Districts". National convention meets quadrennially. Supreme Lodge headquarters is in Chicago. Provides funeral benefits of up to $1,000, no more than two beneficiaries can be designated, and in special circumstances, other benefits can be applied for. Membership in 1922, 8,000, 1934, 7,000, and 1979, 4,500.
=== Internal nasal anatomy === In the midline of the nose, the septum is a composite (osseo-cartilaginous) structure that divides the nose into two similar halves. The lateral nasal wall and the paranasal sinuses, the superior concha, the middle concha, and the inferior concha, form the corresponding passages, the superior meatus, the middle meatus, and the inferior meatus, on the lateral nasal wall. The superior meatus is the drainage area for the posterior ethmoid bone cells and the sphenoid sinus; the middle meatus provides drainage for the anterior ethmoid sinuses and for the maxillary and frontal sinuses; and the inferior meatus provides drainage for the nasolacrimal duct. The internal nasal valve comprises the area bounded by the upper lateral-cartilage, the septum, the nasal floor, and the anterior head of the inferior turbinate. In the narrow (leptorrhine) nose, this is the narrowest portion of the nasal airway. Generally, this area requires an angle greater than 15 degrees for unobstructed breathing; for the correction of such narrowness, the width of the nasal valve can be increased with spreader grafts and flaring sutures.
=== Placebo === Methylene blue has been used as a placebo; physicians would tell their patients to expect their urine to change color and view this as a sign that their condition had improved. This same side effect makes methylene blue difficult to use in traditional placebo-controlled clinical studies, including those testing for its efficacy as a treatment. One approach is to use a low dose, just enough to turn urine blue, as the placebo group. However, a low dose does not guarantee inertness.
Most notably, the oldest samples of European cheese (5500 BC) were found in the region of Kuyavia, and a pot from Bronocice is incised with what is now believed to be the earliest-known portrayal of a wheeled vehicle (3400 BC). Toolmaking became more advanced and material was primarily sourced from quarries and mines in the Świętokrzyskie (Holy Cross) Mountains. Artifacts that originated in this mountain region were excavated as far as Moravia and near the Baltic Sea. It is estimated that the UNESCO-protected neolithic flint mines at Krzemionki, one of Europe's largest, were utilised by the Funnelbeaker and Globular Amphora cultures from 3900 BC to 1600 BC. The only surviving example of ancient parietal art in Poland is at a flint shaft in Krzemionki and features a linear charcoal pictogram of a female figure or deity that has been since associated with fertility.
The Ehrlich pathway refers to this process in which alpha-keto acids are decarboxylated and transformed to aldehydes and to higher alcohols. The temperature of the fermentation process also greatly affects the alcohol content of the resulting product. For example, a study conducted by Pinal et al. found that cultivating two strains at a temperature of 35 °C as compared to a temperature of 30 °C produced more isoamyl alcohol. The higher temperature appears to be favorable for the action of the yeast. The age of the agave plant is also a factor: the older the plant, the greater the production of higher-order alcohols. It was shown in a study that the concentration of amyl alcohol increased by 30% as the plant aged. Conversely, a higher concentration of methanol is found when using younger plants. This change may be due to differences in agricultural practices with plants of different ages.
Sources: en.wikipedia.org
It corresponds to a fragment of the larger protein prothymosin alpha, which is present in many tissues. The isolated 28-amino-acid peptide was originally obtained from thymus preparations, and the pharmaceutical product is synthesized rather than extracted. The term therefore describes both a natural fragment and a manufactured drug substance.
Thymosin alpha-1 is a single defined 28-residue peptide, while the broader family includes unrelated peptides such as thymosin beta-4. The shared name reflects historical isolation from thymus tissue rather than a common structure. Confusion between the two is common in older literature.
No single pathway fully accounts for its reported effects. Several studies describe interaction with innate immune receptors and downstream cytokine changes, but the complete picture is not settled. Open questions remain about which effects occur at physiological concentrations.
It is usually classified as an immunomodulatory peptide rather than a classical hormone. It derives from the larger protein prothymosin alpha and acts mainly on immune cells. The thymosin label covers a group of distinct peptides, so the naming can be misleading.